A shell is fired from cannon. At the instant the shell is just about to leave the barrel, its velocity relative to the barrel is 3m/s, while the barrel is swinging upwards with a constant angular velocity of 2 rad/s. The magnitude of the absolute velocity of the shell is
(a) 3 m/s (b) 4 m/s
(c) 5 m/s (d) 7 m/s